Manufacture of soap bars

ABSTRACT

Continuous preparation of striped soap bars by compressing simultaneously two soap masses of different colours in parallel directions employing a modified double-twin-barrel plodder, provided with partition walls, tubular arrangement and apertured plates, and means for injecting coloured liquid.

United States Patent Grelon 1 May 20, 1975 1 MANUFACTURE OF SOAP BARS [56] References Cited [75] Inventor: Pierre Grelon, Marq-en-Baroenl, UNITED STATES PATENTS France 2,456,141 12/1948 Myerson 425/133 3,398,219 8/1968 Kelley 264/148 X [73] Asslgnee f? ga Cmnpany New 3,608,013 9/1971 lngham 264/245 x 1 3,823,215 7/1974 D'Arcangeli 425 131 x [22] Med: 1974 FOREIGN PATENTS OR APPLICATIONS 1 1 App 442,692 981,373 1951 France 425/131 Related [1.5. Application Data h [62] Division of Ser. No. 303,176, Nov. 2, 1972, 1 M Agmear abandoned ASSlSIanl Exammer ar osen aum [30] Foreign Application Priority Data Nov. 5, 1971 United Kingdom 51476/71 [57] ABSTRACT Continuous preparation of striped soap bars by com- [52] US. Cl. 425/1311; 264/75; 264/245; pressing simultaneously two soap masses of different 425/199; 425/376 colours in parallel directions employing a modified [51] Int. Cl B291 3/12 double-twin-barrel plodder, provided with partition [58] Field of Search 425/131.l, 130, 199, 197, walls, tubular arrangement and apertured plates, and

means for injecting coloured liquid.

5 Claims, 7 Drawing Figures PATENTED MAY 20 I975 SHEET 10F 4 MANUFACTURE OF SOAP BARS This is a division of application Ser. No. 303,176, filed Nov. 2, 1972, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention Manufacture of striped soal bar.

2. Description of the Prior Art Multicoloured, striped or marbled soal bars are known in the art. The preparation of such bars is of course more complicated than the preparation of a one-coloured bar.

Various methods have been applied and suggested for the production of multicoloured soap bars.

SUMMARY OF THE INVENTION The present invention relates to an improved soap plodder, and to a process employing the improved soap plodder for making multicoloured soap bars, especially striped soap bars. The invention also includes soap bars having stripes and multicolouration made by the process.

DESCRIPTION OF THE INVENTION The invention relates to a process and apparatus for the continuous preparation of multicoloured soap bars. The term soap used herein is intended to cover normal soap based on salts of fatty acids, synthetic detergent raw material and mixtures thereof.

According to one aspect of the invention a process for the continuous preparation of striped and marbled soap bars comprises the steps of compressing simultaneously two soap masses of different colours in parallel directions and extruding one soap mass through a system of parallel tubes to form rods, pressing simultaneously the other soap mass into a room surrounding the tubular arrangement and extruding it through an apertured plate at the end of the tubular arrangement, where the two systems of soap rods combine and are further subjected to inward compression and extruded as a striped soap bar.

According to another aspect of the invention an apparatus for carrying out the above process comprises a twin-barrelled soap plodder comprising at least one set of two parallel barrels having a partition wall in between for the provision of two separated streams of soap mass, a cone attached to the barrel-twin outlets and two parallel plates positioned in the cone after the worm compressors, each plate having two groups of apertures, one group being connected by a system of tubes through which the soap mass emerging from one barrel passes, the second group of apertures functioning as outlets for the soap mass emerging from the second barrel. In practice the two parallel plates should be positioned at reasonable distance from each other, so as to obtain a satisfactory and homogeneous structure of the extruded striped soap. It has been found that a distance of 200-300 mm, and preferably of between 250-300 mm, is generally quite acceptable.

Preferably at least one means for colour injection into the barrel is provided for in situ production of coloured soap mass, which enables feeding the two separate barrels of the plodder via the hopper with one and the same soap base. The apparatus can also work without a means for colour injection. In that case the plodder is fed with two differently coloured soap bases made elsewhere, the soap bar obtained being a striped soap bar.

A sharply striped soap bar is also obtained with the process of the invention employing the improved soap plodder if the colour is injected at a position as far as possible from the barrel outlets, preferably immediately after the hopper, feeding the plodder apparatus.

Said arrangement would of course give a better homogeneous distribution of the colour within the soap rather than an arrangement in which the colour is injected nearer the barrel outlets.

The striping appearance of the soap bar may, however, be modified as desired by varying the position of colour injection along the barrel length.

BRIEF DESCRIPTION OF THE DRAWINGS The process and apparatus of the invention will now be further described with reference to the accompanying diagrammatic drawings, in which:

FIG. I shows a longitudinal view through the essential part of the soap extrusion apparatus according to the invention and FIG. 2 shows a perspective view of one embodiment of the device comprising the apertured plates with tubular arrangement.

FIG. 3 shows a cross-sectional view of the soap mass produced by the process of the invention just before passing the eye plate at the end of the plodder, using an end plate with the above aperture arrangement.

FIG. 4 shows three orifice positions of eye plate producing different striations in the fianl soap tablet. D and E can be obtained simultaneously by using an eye plate with two apertures.

FIG. 5 shows a cross-sectional view of a striped soap bar made according to the process of the invention extruded through a rather conventionally shaped orificed eye plate.

FIG. 6 shows a plain upper view of the striped soap tablet stamped from this bar.

FIG. 7 shows another striped soap tablet stamped from a bar extruded through orificed eye plate E of FIG. 4.

DETAILED DESCRIPTION OF THE DRAWINGS Referring now to FIG. 1: Cone 1 is attached to the barrel twins 2 and 3 enclosing two worm compressors 7 and 8, and separated by a partition wall 16. The apertured front plate 4 is positioned in cone 1 near the outlets of barrels 2 and 3. The apertured end plate 5 is positioned further down-stream in cone 1; the system of tubes 6 connecting one group of apertures in both plates is positioned horizontally and parallel to the cone axis. Soap mass A transported by worm compressor 7 emerging from barrel 2 passes through openings 9 (see also FIG. 2) into room 10 and is pressed through apertures 11 (see also FIG. 2) into room 12. Soap mass B (having a colour distinct from A) transported by worm compressor 8 and emerging from barrel 3, passes through tubes 6 and is pressed into room 12, meeting soap mass A. The combined soap mass is extruded through the orificed eye plate 13 to form a soap bar having a striped appearance Separate streams of soap masses A and B passing through plate 4 are effected by partition wall 14.

Pressure gauge 15 positioned on the cone in between the two apertured plates provides an efficient control of the pressure in the cone.

In FIG. 2 a model arrangement of apertures is shown on end plate 5.

The tubes 6 are preferably longitudinally positioned substantially around the central axis of the cone, to give the least capacity reduction of the plodder. Depending on the capacity and size of the plodder the number of tubes may vary from to about 40.

The total surface area of the tube outlets for soup B with respect to the total surface area of apertures for soap A on end plate 5 should be arranged so as to reasonably correspond with the pressures exerted on the soap masses by the two worm compressors.

It has been established that a surface area of the tube outlets for soap B of 55-60% against a surface area of apertues for soap A of 40-45% on the end plate gives very good processing into soap bars of quite satisfactory appearance.

A satisfactory aperture arrangement on the end plate such as shown in FIG. 2 may consist eg of:

} for soap B for soap A 12 holes of 26 mm diameter 12 holes of 8 mm diameter 10 rectangular slots of9 to 32 mm which arrangement has a surface area ratio of 57% B to 43% A.

In fact this aperture arrangement determines in an essential way the colour pattern in the soap bar and its striped appearance.

Quite attractive variations in the striped appearance meeting different consumer preferences can also be obtained by simply mounting different orificed eye plates on the plodder outlet through which the soap mass is extruded.

FIGS. 3, 4 and 5 illustrate some cross-sectional views of the many variations of colour patterns within the soap obtained from one aperture arrangement on the end plate, by using different orificed eye plates.

It is to be understood that when preparing the striped soap bar according to the process of the invention, the two differently coloured soap masses should be compressed and transported by the worm compressors in the plodder at about the same speed, so as to avoid the shearing of stripes, causing irregularities in the pattern.

In order to obtain a good regularity of stripes it is also desirable to operate the plodder at a temperature of about 30-50C, preferably in the range of 3545C, depending on the fat charge or composition of the soap. Too high a temperature during plodding would cause the soap mass to be too soft for plodding and would consequently result in bleeding of the stripes. It is also important that the temperature during plodding should be maintained at a constant level, otherwise irregularities in stripes occur.

It has further been established that a feed ratio of 25-75% by weight of soap A and 75-25% by weight of soap B generally produces bars of satisfactory striping appearance.

Normally the compositions of the soap base, which can be processed in the apparatus of the invention do not differ from those used for manufacturing white or one-coloured soap bars. Although the improved plodder is preferably used for processing true soap bars comprising sodium soap derived from mixtures of coconut and tallow fatty acids, it is equally applicable to the processing of bars composed of other synthetic detergent mixtures having a comparable consistency of true soaps.

Examples of suitable soap compositions are sodium soaps derived from mixtures of 30-90% by weight of tallow fatty acids and -10% by weight of nut oil fatty acids, which mixtures can be super-fatted with for example free fatty acids up to 20% by weight of the total composition.

Examples of synthetic detergents which can be processed according to the invention include the alkali metal salts of higher (C -C fatty alcohol sulphuric acids, higher (C -C alkyl benzene sulphonates, the sodium or potassium salts of higher fatty acid mono 'glyceride sulphuric acids having 14-18 carbon atoms in the fatty acid groups, ethylene oxide condensation products of (C -C alkyl phenol or of (C -C fatty alcohols, and the alkali metal sulphates of ethoxylated fatty alcohols.

An embodiment of the invention will now be described by way of example.

Milled white soap is fed via a hopper into the worms of a modified double twin-barrel vacuum plodder. Due to the partition wall between the worms two streams of soap now travel separately through the barrels in parallel direction. Colour is injected into one barrel at a point approximately half-way down the first set of barrel-twins. The soap masses A and B pass again separately a vacuum chamber and travel further through the second set of barrel-twins as shown in FIG. 1.

The process according to the invention does not produce only stamped soap tablets having a striped appearance, but can also be employed to produce tablets having a pattern of stripes emanating from the centre if the cut bars leaving the extrusion apparatus are stamped in axial direction, the term axis meaning the symmetry axis of the bar leaving the extrusion apparatus.

EXAMPLE Component by weight superfatted chips 98.40 titanium dioxide (white pigment) 0.30 preservative 0.06 perfume 1.22 optical bleach 0.02

The mixture of soap chips, white pigment, optical bleach, preservative and perfume was milled in a conventional soap mill and the milled chips were fed into a 1.5 tons/hour capacity double-twin-barrel plodder modified according to the invention by the provision of partition walls, means for colour injection and a tubular arrangement with apertured plates as described above and illustrated in the accompanying darawings.

Into soap A a 3% aqueous soluton of a mixture of blue and green dyes, Monastral fast blue and Monastral fast green (Trade Marks) was injected at a rate of 10 litres per ton of soap throughput.

The means for colour injection was positioned at a point half-way down the first set of barrel-twins. The tubular arrangement and apertured plates used were those as shown in FIG. 2.

The blue striped white bar, extruded from the apparatus through a conventional eye plate as shown in FIG. 5, was stamped into tablets.

I claim:

1. An apparatus for the continuous preparation of multi-colored detergent bar which comprises a twinbarrel soap plodder comprising at least one set of two parallel barrels, having a partition wall in between for the provision of two separated streams of soap mass, a cone attached to the barrel-twin outlets and two parallel plates positioned in the cone after the worm compressors, each plate having two groups of apertures, one group being connected by a system of tubes through which the soap mass emerging from one barrel passes, the second group of apertures functioning as outlets for the soap mass emerging from the second barrel.

2. Apparatus according to claim 1, in which there is provided at least one means for colour injection into at least one barrel positioned at a point along the barrel length.

3. Apparatus according to claim 1, in which the two parallel plates are positioned at a distance of 200-300 mm from each other.

4. Apparatus according to claim 1, in which the tubes connecting the two apertured plates are positioned longitudinally and substantially around the central axis of the cone.

5. Apparatus according to claim 1, in which the surface area of apertures forming the tube outlets on the down-stream positioned plate is 55-60%, and the surface area of the free apertures if 40-45% of the total surface area of apertures. 

1. An apparatus for the continuous preparation of multi-colored detergent bar which comprises a twin-barrel soap plodder comprising at least one set of two parallel barrels, having a partition wall in between for the provision of two separated streams of soap mass, a cone attached to the barrel-twin outlets and two parallel plates positioned in the cone after the worm compressors, each plate having two groups of apertures, one group being connected by a system of tubes through which the soap mass emerging from one barrel passes, the second group of apertures functioning as outlets for the soap mass emerging from the second barrel.
 2. Apparatus according to claim 1, in which there is provided at least one means for colour injection into at least one barrel positioned at a point along the barrel length.
 3. Apparatus according to claim 1, in which the two parallel plates are positioned at a distance of 200-300 mm from each other.
 4. Apparatus according to claim 1, in which the tubes connecting the two apertured plates are positioned longitudinally and substantially around the central axis of the cone.
 5. Apparatus according to claim 1, in which the surface area of apertures forming the tube outlets on the down-stream positioned plate is 55-60%, and the surface area of the free apertures if 40-45% of the total surface area of apertures. 